垂直能量螺旋度在双流机场雷暴预报中的应用

文章引入垂直能量螺旋度指数的概念,并利用NCEP 1°×1°再分析资料,将其应用于双流机场2011年5月8—9日出现的雷暴天气过程,并对2009—2012年双流机场出现的32次雷暴天气过程进行统计,验证垂直能量螺旋度指数的有效性及普适性。结果表明,该指数综合反映了对流天气发生时的热力效应和动力效应,有明确的物理意义,是诊断和预报强对流天气的有效指数;垂直能量螺旋度对预报双流机场未来3h以内的雷暴天气有一定的指示意义,雷暴天气一般出现在垂直能量螺旋度大于0.62×10-5J·m·kg-1·s-2的条件下。

Application of Vertical Energy Helicity on Forecasting Thunderstorm in Shuangliu Airport

A new concept of vertical energy helicity index was proposed by this paper, in order to prove the ef- fectiveness and universality of vertical energy helicity index, by using NCEP 1°×1° reanalysis data, the vertical energy helicity index was applied to a thunderstorm progress which took place in Shuangliu airport from May 8th to 9th in 2011, and 32 thunderstorm cases which occurred during 2009-2012 are analyzed. The results showed that the index could reflect the thermal effect and dynamic effect of convective weather, so the index had certain physical meaning which also was a effective index in the diagnosis and prediction of severe convective weather. Vertical energy helicity would provide with good indicative significance for the forecasting of thunderstorm within the future 3 hours, thunderstorm weather often occurs when vertical energy helicity index larger than 0.62×10^-5J·m·kg^-1·s^-2.